I'm replacing my existing GARAGE with a new timber one, 12ft square. The site slopes a lot, 3 feet drop over the 12 feet, and it's not feasible to build a retaining wall and backfill to get a level base, so I intend to put in some vertical posts 4x4 and span these with 6x2 beams. The big question is: how many cross beams do I put in? One every 2/4/6 feet? Advice from suitably-qualified/experienced/extrovert/just plain vocal members, please. PS it'll house at least one bike, plus tools etc. Generator, compressor and so on. The floor will be 22mm t&g with cross-members every 1.5-2ft.